1458 results about "Space group" patented technology

A ferromagnetic tunnel junction structure comprising a first ferromagnetic layer, a second ferromagnetic layer, and a tunnel barrier layer that is interposed between the first ferromagnetic layer and the second ferromagnetic layer, wherein the tunnel barrier layer includes a crystalline non-magnetic material having constituent elements that are similar to those of an crystalline oxide that has spinel structure as a stable phase structure; the non-magnetic material has a cubic structure having a symmetry of space group Fm-3m or F-43m in which atomic arrangement in the spinel structure is disordered; and an effective lattice constant of the cubic structure is substantially half of the lattice constant of the oxide of the spinel structure.

In a preferred embodiment, a freestanding vertical horticultural apparatus for commercial and/or home use for growing of plants in containers includes a plurality of containers arranged in a plurality of mutually vertically spaced groups which are rotatably supported in brackets by an elongated vertical spindle through which is routed a pressurized fluid supply line which is coupled to a spray emitter by way of a flow adjustment valve. At a flow rate determined by the valve, the emitter sprays irrigation fluid inside a hollow distributor body positioned at the top of the apparatus. The lower portion of the distributor body is segmented into a plurality of sumps, each of which feeds a substantially uniform quantity of the fluid under gravity to each respective one of the containers by way of a respective fluid delivery tube, one of which is coupled to the lower portion of each sump.

The invention relates to a sulfurized gallium and barium monocrystal as well as a growing method and an infrared nonlinear optical device thereof. A molecular formula of the sulfurized gallium and barium monocrystal is BaGa4S7, the sulfurized gallium and barium monocrystal belongs to the field of rhombic systems, a space group is Pmn21, and a cell parameter is as follows: a=14.755 A, b=6.228 A, c=5.929 A, and alpha=beta=gamma=90 DEG. The nonlinear optical materials are prepared by adopting a crucible decent method to obtain compositions and monocrystals of the same and can be used for manufacturing a secondary harmonic generator, an upper frequency converter, a lower frequency converter and an optical parametric oscillator.

The invention provides a preparation method of nitrogen-doping ordered mesoporous carbon materials. According to the method, rich-hydroxyl saccharide carbohydrate is used as carbon sources, ammonia water is used as nitrogen sources, amination reaction under the hydrothermal condition is adopted for preparing rich-nitrogen precursors, mesoporous silica molecular sieves SBA-15 (space group P6mm) are used as templates, and the nitrogen-doping ordered mesoporous carbon materials in two-dimensional orthohexagonal ordered mesostructures are prepared through multi-time wetting combined with the high-temperature themolysis technology.

A borate single crystal which can stably perform light wavelength conversion with high efficiency down to the ultraviolet region is represented by the chemical formula (A2O).(B2O3)x, and is an orthorhombic crystal belonging to the P212121 space group, wherein A includes two elements selected from the group consisting of Li, Na, K, Rb, and Cs, and 1.5<x<2.5.

The invention relates to a spinel type high-entropy oxide electrode material and a preparation method thereof, and belongs to the field of nanomaterial preparation and new energy. The chemical formulaof the high-entropy oxide electrode material is one of (FeCoNiCrMn)O, (FeZnNiCrMn)O, (FeCoZnCrMn)O and (FeCoNiCrMnCu)O. The preparation method includes the steps of 1) mixing and ball-milling iron oxide, chromium oxide, manganese oxide and M metal oxide, wherein the M metal oxide is two or more of nickel oxide, zinc oxide, copper oxide and cobalt oxide; and 2) carrying out high-temperature calcination, and obtaining the spinel type high-entropy oxide electrode material by adopting a cooling mode of furnace cooling, air quenching and liquid nitrogen quenching. The particle diameter of the high-entropy oxide is 100-500nm, and the high-entropy oxide is determined to be in a spinel structure according to XRD; and the space group of the material is Fd-3m, and the specific surface area is 5-100m<2>g<-1>.

The invention relates to a nonlinear optical crystal of a potassium borate chloride compound and a preparation method as well as application thereof. The chemical formula of the compound is K3B6O10Cl, and the molecular weight of the compound is 377.61. The crystal does not have a symmetric center and belongs to a trigonal system and a space group R3m, and cell parameters are as follows: a=10.0624(14), b=10.0624(14), c=8.8361(18), Z=3, and V=774.8 (2). The powder frequency-doubled effect reaches about 3 times of KDP(KH2PO4), the Mohs hardness is 4-5, and the light transmission waveband is 165nm-3460nm. A solid phase reaction method is used for synthesizing the compound, and a cosolvent method is used for growing the crystal. The crystal has the advantages of simple operation, low cost, large size, short growth cycle, few inclusion enclaves and larger mechanical hardness, and can be cut, polished, processed and saved easily. The crystal is used for generating twofold frequency or three-fold frequency or fourfold frequency or fivefold frequency harmonic light output for laser beams of which the wavelength is 1064nm.

The invention relates to a nano-high-entropy alloy electrocatalyst and a preparation method thereof, and belongs to the technical field of new material preparation. The material is composed of a three-dimensional porous carbon substrate and FeCoNiCrCu high-entropy alloy nanoparticles loaded on the three-dimensional porous carbon substrate; the nanoparticles are an FeNi alloy structure monoclinic system, and the space group is Pm6; the molar ratio of Fe to Co to Ni to Cr to Cu is 1:1:1:1:1. The preparation method comprises the following steps: 1) dissolving a template agent-sodium chloride, a carbon source, and urea with deionized water, adding a doping source, magnetically stirring and freezing until totally solid, and then performing vacuum drying; 2) performing heat treatment and then cooling to room temperature to obtain powder; 3) washing, filtering and drying the powder to obtain the nano-high-entropy alloy electrocatalyst; 4) producing the nano-high-entropy alloy electrocatalyst into a working electrode and performing electrochemical performance test. The diameter of the nano-high-entropy alloy nanoparticles is 10 to 100 nm; according to a reaction of oxygen evolution through catalysis of the high-entropy alloy electrocatalyst, the initial potential is 1.50 to 1.63 V, the overpotential is 360 to 460 mV when the current density is 10 mA cm<-2>, and the Tafel slope is 70 to 120 mV dec<-1>.

The invention relates to the technical field of ceramic powder preparation, and specifically discloses RE3Ta/NbO7 (Rare-Earth Tantalite/Niobate) ceramic powder. The preparation method comprises the following steps: carrying out ball milling on RE2O3 powder, Ta2O5 powder or Nb2O5 powder, and carrying out solid-phase reaction, thus obtaining a target phase; mixing the target phase with an organic adhesive, thus forming slurry; drying by adopting a high-temperature spray pyrolysis method, thus obtaining sphere-like powdery particles; sintering, thus obtaining the RE3Ta/NbO7 ceramic powder. A chemical general formula of the RE3Ta/NbO7 ceramic powder is RE3TaO7/RE3NbO7. A crystal structure of the RE3Ta/NbO7 ceramic powder is an orthorhombic phase, the space group of a crystal lattice is C2221,the particle diameter is 10 to 50 mum, and the RE3Ta/NbO7 ceramic powder is spherical. By adopting the technical scheme disclosed by the invention, the RE3Ta/NbO7 ceramic powder which can meet APS (Atmospheric Plasma Spraying) technical requirements can be obtained.

A Group IIIA element fluoride-containing coating comprising a Group IIIA element fluoride phase which contains at least 50% of a crystalline phase of the orthorhombic system belonging to space group Pnma is formed on a member for imparting corrosion resistance so that the member may be used in a corrosive halogen species-containing atmosphere. When the state of a crystalline phase is properly controlled, the coating experiences only a little color change by corrosion. A Group IIIA element fluoride-containing coating having a micro-Vickers hardness Hv of at least 100 is minimized in weight loss by-corrosion.

The invention relates to crystals of an insulin analog in which asparagine (Asn) in position B3 of the B chain is replaced by a naturally occurring basic amino acid residue and at least one amino acid residue in the positions B27, B28 or B29 of the B chain is replaced by another naturally occurring neutral or acidic amino acid residue, where phenylalanine (Phe) in position B1 of the B chain can optionally be absent, the crystals being present in the space group R3 (No. 146) with the cell axes A=81.5 ű1 Å and C=33.3 ű1 Å, their preparation and use, and a pharmaceutical composition comprising these crystals.

The invention discloses a porous silicon material, and a preparation method and an application thereof. The porous silicon material is mainly prepared by mechanical milling and acid etching of metallurgical iron-silicon alloy as a raw material; the dimension of the porous silicon material is in micron/submicron level; the porous silicon material has a diamond structure, belongs to an Fd-3m (227) space group, and has a reaction phase which can react with lithium (Li); a large number of hierarchical porous structures with different dimensions are evenly distributed in the surface and the inside of the porous silicon material; the porous silicon material can be used as a lithium ion battery anode active material, and shows the characteristics of high (first) coulombic efficiency, high capacity, excellent cycling stability and the like when applied to a lithium ion battery; meanwhile, the preparation technology of the porous silicon material is simple, and can be carried out only by conventional equipment; the used raw materials are cheap and available; the technological process is easy to control; and the porous silicon material is good in repeatability, high in productivity, stable in product quality and suitable for large-scale production.

The invention discloses a cyclodextrin metal-organic framework compound and its preparation method and use. The cyclodextrin metal-organic framework compound has a chemical formula of Na(C42H64O35). 11H2O (Na-CD-MOF), is a monoclinic crystal and has a P2<1> space group and cell parameters of a=15.2372(5)A, b=10.5956(5)A, c=20.2018(5)A, alpha=Y=90.0371, beta=108.2235 degrees and V=3097.91719A<3>. The crystal has a white color and comprises one beta-cyclodextrin, one Na<+> ion and eleven crystal water molecules. The invention prepares the novel degradable Na-beta-cyclodextrin metal-organic framework molecule without toxic or side effect on the human body. Through a grinding method, the ASP-Na-CD-MOF clathrate is prepared.

The invention relates to a non-linear optical crystal-sodium beryllate borate, a growth method and application thereof. A chemical formula of the sodium beryllate borate is NaBeB3O6, the sodium beryllate borate belongs to an orthorhombic system, a space group is Pna21, cell parameters are that a is equal to 9.1531*, b is equal to 11.9337*, c is equal to 4.3724*, alpha is equal to beta, gamma and 90 DEG, and z is equal to 4, and the unit-cell volume is that V is equal to 477.60*<3>. The frequency multiplication coefficient of the sodium beryllate borate is 1.22 times of that of LiB3O5(LBO). The ultraviolet absorption edge of the sodium beryllate borate is shorter than 190nm. A solid-phase synthesis method is adopted for sintering at high temperature to obtain a NBB compound. A monocrystal can be successfully grown by using a molten salt method and taking Na2O-B2O3 or NaF-B2O3 as a fluxing agent. The NaBeB3O6 has non-linear optical effect, cannot be dissolved into dilute acid, has good chemical stability, can be widely applied in various non-linear optical fields, and can develop the non-linear optical application of deep ultraviolet wavebands.

The invention relates to a large-sized bismuth barium borate non-linear optic crystal, which belongs to the orthorhombic system with a space group equal to Pna21 and a molecular formula equal to BaBiBo4. The crystal is made from a mixed system of bismuth barium borate, fluxing agent Bi2O3 and BaB2O4, or BaO and Bi2O3; the nonlinear optical effect of the crystal is approximately five times of that of (KH2PO4) KDP; and the crystal is transparent within a wave band of between 200 and 3,000 nm, and has the large size with 1 to 100mmx1 to 100mmx1 to 100mm. The large-sized bismuth barium borate non-linear optic crystal has the advantages of quick making speed, simple operation, low cost, large-sized and transparent crystal made by the non-linear optic crystal, wide light-transmission wave band, ideal mechanical property, infrequent fragmentation, stable physicochemical properties, no deliquescence and easy processing and preservation; moreover, the non-linear optic crystal can be used to make non-linear optical devices such as a multiple frequency generator, an upper frequency converter or a lower frequency converter and an optical parametric oscillator.

The invention relates to a large size potassium strontium borate nonlinear optical crystal, the preparation and use thereof. The formula of the crystal is: KSr4B3O9, which belongs to rhombic system, the space group is Pna2(1), and the molecular weight is 566.01, and the crystal size is 10-60mmx10-60mmx10-60mm. The preparation contains the following steps of: evenly mixing the potassium strontium borate compound with a fusing assistant, heating, maintaining the constant temperature, cooling to the saturation temperature and obtaining a mixture solution, placing a seed crystal into the mixture solution, lowering the temperature to the saturation temperature to obtain the required crystal, and subsequently extracting the crystal from the liquid level, cooling to room temperature, and finally obtaining the large size potassium strontium borate nonlinear optical crystal. The nonlinear optical effect of the crystal is approximately the same as the KDP, the transparent optical band is 220nm-3000nm. The crystal is simple in operation, low in cost, large in crystal size, short in growth period, less in coating, high in laster damage threshold, good in mechanical property, firm, stable in physicochemical properties, uneasy to deliquescence, convenient for processing and storage, or the like. Accordingly, the nonlinear optical crystal of the invention can be abroadly applied in nonlinear optical devices such as frequency doubler, optical parametric oscillator or the like.

The invention relates to the technical field of preparation of ceramic powder, and discloses rare earth tantalum/niobate (RETa/NbO4) ceramic powder and a preparation method thereof. The chemical general formula of the rare earth tantalum/niobate (RETa/NbO4) ceramic powder is RETa/RENbO4, the crystal structure of the ceramic powder is the orthorhombic phase, the crystal lattice space group is C2221, the particle size is 10-70 microns, and the ceramic powder is spherical. In the preparation process, raw materials are subjected to ball milling, after a high temperature solid phase method is adopted for a reaction the processed raw materials, a solvent and an organic adhesive are mixed to obtain paste C, after centrifugal atomization, dry material particles are obtained, resintering is conducted, and the rare earth tantalum/niobate (RETa/NbO4) ceramic powder meeting the requirements of an APS technology for ceramic powder is obtained.

The present invention belongs to the field of inorganic advanced material technology, in the concrete, it relates to a kind of nano crystal large-diameter mesopore oxide material and its preparation method. Said mesopore oxide material is synthesized by using inorganic precursor and organic template agent molecules through a self-assembly process including organic solvent evaporation and induction treatment in the acidic environment, its space group structure is two-dimensional hexagonal structure, three-dimensional hexagonal structure and three-dimensional cubic structure, its pore diameter range is 1-18nm, BET specific surface area is 50-800 sq.m/g and its thermal stability is higher than 400 deg.C.

The present invention provides for thermally stable forms of 2,4-diamino-5-methyl-6-[(3,4,5-trimethoxyanilino)methyl] quinazoline, or trimetrexate. A crystalline 2,4-diamino-5-methyl-6-[(3,4,5-trimethoxyanilino)methyl] quinazoline monohydrate, or trimetrexate monohydrate, belonging to the space group P+E,ovs 1+EE (#2) and having a triclinic cell with dimensions of about a=7.699 ANGSTROM , b=9.606 ANGSTROM and c=13.012 ANGSTROM is disclosed. A novel Schiff base compound, 2,4-diamino-5-methyl-6-[(3,4,5-trimethoxyphenylimino)-methinyl]quinazoline, is also disclosed. The present invention further provides novel methods of producing stable trimetrexate free base compounds, including crystalline trimetrexate monohydrate. The crystalline monohydrate form provides increased stability over the anhydrous form.

A method provides X-ray diffraction data suitable for integral detection of a twin defect in a strained or lattice-matched epitaxial material made from components having crystal structures having symmetry belonging to different space groups. The material is mounted in an X-ray diffraction (XRD) system. In one embodiment, the XRD system's goniometer angle Ω is set equal to (θ_B−β) where θ_B is a Bragg angle for a designated crystal plane of the alloy that is disposed at a non-perpendicular orientation with respect to the {111) crystal plane, and β is the angle between the designated crystal plane and a {111} crystal plane of one of the epitaxial components. The XRD system's detector angle is set equal to (θ_B+β). The material can be rotated through an angle of azimuthal rotation φ about the axis aligned with the material. Using the detector, the intensity of the X-ray diffraction is recorded at least at the angle at which the twin defect occurs.

The invention relates to a copper-doped all-inorganic halogen perovskite fluorescent material and a preparation method and application thereof. The material has structural formula CsPb1-xCuxBr3, wherein X is in the range of 0-1; the material is a light yellow or yellow powder, and in cubic phase, and has a space group as below. The method is as below: dissolving in an organic solvent at high temperature for further reaction, washing with a hexane or toluene solvent by multiple times, purifying to obtain the copper-doped all-inorganic halogen perovskite fluorescent material with size of 10-30nm. By measuring of the UV visible (wavelength range of 350-700nm) and fluorescence spectra (excitation wavelength is 360nm with), with the increase of doping amount of copper, the absorption wavelength and corresponding fluorescence emission wavelength show the red shift phenomenon, at the same time, the fluorescence quantum yield also changes. The preparation method of the invention is simple, green and environment-friendly, and has good application potential in the preparation of LED.

The invention relates to a rare earth oxide crystal and a preparation method thereof. The structural general formula of the crystal is (LnxRe1-x)2O3, the crystal belongs to a cubic crystal system, the space group is Ia3, and the crystal is in a bixbyite structure. The preparation method of the rare earth oxide laser crystal comprises the following steps of: firstly, manufacturing polycrystalline materials by taking Re2O3 and Ln2O3 as raw materials; then, manufacturing material bars; and filling the material bars into an optical floating zone growing furnace for growing according to a floating zone method. The method of the invention has high speed and short cycle, a crucible is not needed in crystal growth, the pollution on the crystal is reduced, and the growing crystal has high transparency and less cracks and is suitable for laser devices.

The invention relates to BaMgBO3F non-linear optical crystal, a preparation method and applications thereof. The crystal belongs to a hexagonal system and a P-6 space group, and has the following cell parameters: a=5.06, c=4.28 and z=1. Zn2+ in the crystal is coordinated by three Os and two Fs. The frequency doubling effect is equivalent to LBO. The decomposing temperature is 860+/-10 DEG C, and the crystal does not generate deliquescence in air, and is not dissolved in the water solution with the pH valve of 2-12 at normal temperature. The method has the following preparation steps of: mixing the BaMgBO3F with a fluxing agent, and heating into a melt body; forming seeds under the temperature of 0.5-5 DEG C above the temperature of the saturation point of the melt body; subsequently, decreasing the temperature to 0-1 DEG C below the temperature of the saturation point, and rotating along with decreasing temperature to grow the crystal; separating the melt body when the crystal is grown to the required size, and decreasing to the room temperature to obtain the BaMgBO3F single crystal. The crystal has the equivalent frequency doubling effect with LiB3O5 (short for LBO), and can be used as the frequency doubling crystal in the optical parametric oscillator or the harmonic generator.

The present invention relates to positive electrode active substance particles comprising a compound having at least a crystal system belonging to a space group of R−3m and a crystal system belonging to a space group of C2/m, and boron, wherein the compound is a composite oxide comprising at least Li, Mn, and Co and/or Ni; a relative intensity ratio [(a)/(b)] of a maximum diffraction peak intensity (a) observed at 2θ=20.8±1° in a powder X-ray diffraction pattern of the positive electrode active substance as measured using a Cu-Ka ray to a maximum diffraction peak intensity (b) observed at 2θ=18.6±1° in the powder X-ray diffraction pattern, is 0.02 to 0.5; a content of Mn in the positive electrode active substance particles is controlled such that a molar ratio of Mn/(Ni+Co+Mn) therein is not less than 0.55; and the positive electrode active substance particles comprise the boron in an amount of 0.001 to 3% by weight. The positive electrode active substance particles of the present invention are produced by calcining a mixture comprising precursor particles comprising Mn, and Ni and/or Co, a lithium compound and a boron compound at a temperature of 500 to 1500° C. The positive electrode active substance particles of the present invention can provide a secondary battery which can be improved in charge/discharge capacity and cycle characteristics.

A positive active material for a lithium secondary battery contains a lithium-transition metal composite oxide represented by a composition formula of Li_1+αMe_1−αO₂ (Me is a transition metal element including Co, Ni, and Mn; 1.2<(1+α)/(1−α)<1.6). A molar ratio (Co/Me) of Co contained in the Me ranges from 0.24 to 0.36, and when a space group R3-m is used for a crystal structure model based on an X-ray diffraction pattern, a half width of a diffraction peak that attributes to a (003) line ranges from 0.204° to 0.303°, or a half width of a diffraction peak that attributes to a (104) line ranges from 0.278° to 0.424°.

The invention relates to an inorganic nonlinear optical material lead iodo-borate crystal, and a preparation method and application thereof, belonging to the field of inorganic chemistry as well as the field of material science. The chemical formula of the lead iodo-borate crystal is Pb2B5O9I, and the molecular weight is 739.35; the lead iodo-borate crystal belongs to an orthorhombic crystal system and a space group Pnn2; and the unit cell parameters are as followings: alpha = 90 DEG, beta = 90 DEG, gamma = 90 DEG, and Z = 4. The lead iodo-borate crystal is synthesized by a one-step self fluxing method, which comprises the following steps: mixing lead raw materials consisting of oxide, lead iodide and boron oxide with self flux consisting of PbO and B2O3 which are 50-150% excess, wherein the molar ratio of of PbO:PbI:B2O3 is 3:1:5; adding the mixture to a vacuum sealed container; insulating heat at 700-900 DEG C for 5-48 hours; and slowly cooling to room temperature at the speed of lower than 10 DEG C/hour to obtain an end product lead iodo-borate crystal. The lead iodo-borate crystal has excellent nonlinear optical performance, and the second harmonic generation (SHG) coefficient of the crystal powder is 1.4 times that of KTP (kalium titanium phosphate).